<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8" />
    <title>统计成绩最大值和最小值</title>
</head>
<body>
    <script>
        var arr = [83, 75, 65, 59.5, 92];
        var sum = 0;
        var max = min = arr[0];
        for (var i=0; i<arr.length;i++){
            sum +=arr[i];
            if(arr[i] > max){
                max = arr[i];
            }
            if(arr[i] < min){
                min  = arr[i];
            }
            console.log(sum);
        }
        document.write('5门成绩分别是：' +arr +'<br/>');
        document.write('总分是' +sum +'<br/>');
        document.write('平均分是' +(sum/i) +'<br/>');
        document.write('最高分' + max +'<br/>');
        document.write('最低分' + min);
    </script>
</body>
</html>